These boring, trite, melba-toast retorts will help you deflect an impertinent question or wiggle out of any jam, no matter how uncomfortable. Learn them. Memorize them. Use them. They're your friends.
We live in an enlightened time. Love, chemistry, and relationships transcend outdated, insulting, and misogynistic "rules." We're smarter than that. We're better than that. So, eff tradition--go for it.
Or...
You're eating his balls for breakfast.
The plan has lots of segments, boat ride, dinner, drinks with friends, hotel, and a few things the next day. Is it better to ask her pretty early on in the night, and enjoy everything I've planned? or allow the suspense to build up (even though she'll know something is up) and ask toward the end?
There are only a few things we stress as really, really, really important, the kind of shit you can't ignore or blow off. The proposal is one of these things. Luckily, we got some help.
It will be remembered forever. It will be talked about (from your wife to her friends) forever. And it all comes down to your creativity and your execution.